Yale Researcher to Scrutinize Medtronic Infuse Studies

Medtronic Inc. is hoping a “rock star” Yale University researcher will be able to quiet the controversy surrounding its Infuse bone growth product. Over the past year, critics of Medtronic have alleged that researchers paid by the device maker downplayed serious side effects, including cancer, in clinical trials for Infuse. Medtronic has also been plagued by allegations that it paid illegal kickbacks and questionable royalties to doctors to encourage them to use Infuse for off-label, or unapproved, treatments.

Medtronic Infuse, which contains a bioengineered bone growth protein called rhBMP-2, was approved by the U.S. Food & Drug Administration (FDA) in 2002 as a treatment for anterior approach lumbar fusion. However, as weâ€™ve reported previously, Infuse was widely used in off-label procedures, such as cervical spine (neck) surgeries. In July 2008, however, the FDA warned that Infuse Bone Graft and similar products had caused serious problems when they were used off-label in cervical spine (neck) surgeries.

The latest controversy to erupt around Infuse came earlier this month, when a frequent critic of the product warned that its association with cancer might be stronger than originally thought. In a study presented at the North American Spine Society meeting, Dr. Eugene Carragee reported that his review of a Medtronic-funded study indicated that a higher-dose formulation of Infuse, known as Amplify, had been linked to a significantly higher number of cancers than were found among those who received a traditional bone graft. Amplify was actually rejected by the FDA because of its association with cancer.

In an interview with The New York Times, Carragee said the cancer findings could have serious implications for people receiving Infuse. Doctors often administer Infuse off-label at levels significantly above the recommended dosages, ones that approach or exceed the amount of rhBMP-2 found in a dose of Amplify, he said.

The Spine Society presentation was the second time Carragee raised questions about Medtronic-sponsored research for rhBMP-2. This past June, a Spine Journal article he authored reported that Medtronic-paid surgeons had failed to report serious complications from Infuse, including cancer, sterility in men, infections, bone dissolution and worsened back and leg pain. The article said complications occurred in 10 to 50 percent of patients who got the product in 13 Medtronic-funded clinical trials between 2000 and 2010.

The U.S. Senate Finance Committee has been investigating Infuse for several years, and recently â€“ thanks to Carrageeâ€™s Spine Journal article â€“ demanded Medtronic turn over records detailing payments made to infuse researchers. Meanwhile, the U.S. Justice Department is investigating off-label use of Infuse.

It was Carragee’s June expose that prompted Medtronic to look to Yale University, and Dr. Harlan Krumholz, a doctor Forbes magazine once referred to as “he most powerful doctor you never heard of.” According to a report from the Minneapolis Star-Tribune, Krumholz and his team at Yale will address fundamental questions: Does Infuse work? Is it safe?

“I’m not seeking to address how the product was marketed,” Krumholz told the Star-Tribune. “I’m just sticking to the science. I’m trying to set in place a new way of doing business.”

Medtronic has promised to give Krumholz and his team all the available medical records of Infuse-treated patients, and the team will choose two independent research organizations to subject the data to further investigation. The probe will assess Infuse’s safety performance, including side effects such as cancer, excessive bone growth, male sterility and “retrograde ejaculation,” the Star-Tribune said. The results of the Yale project will be released by mid-2012.

Medtronic also said it will make the data available to other researchers who could access it through a website.

It remains to be seen if even positive results from Krumholzâ€™s review will quiet Medtronicâ€™s critics. While many experts acknowledge the unprecedented nature of the Yale project, and praised its scope, they have little praise for Medtronicâ€™s handling of Infuse.

“I think it’s ridiculous that the company is saying it’s now going to complete an independent study [on Infuse],” Dr. Charles Rosen, a California spine surgeon and founder of the Association for Medical Ethics, told the Star-Tribune. “That implies the previous studies weren’t independent.”